Table of Contents
Which requires more work lifting a 50 kg sack a vertical distance of 2 m or lifting a 25 kg sack a vertical distance of 4 m g 10 m/s 2?
Which requires more work- lifting a 50-kg sack a vertical distance of 2 m or lifting a 25-kg sack a vertical distance or 4 m? Both are the same amount of work because the force x distance is the same for each.
How much work must the brakes of a car supply to stop a car moving four times as fast?
A four times as fast car has 16 times as much DE and will require 16 times as much work to stop, and 16 times as much stopping distance.
When a car is raised up on a hydraulic lift it gains potential energy if you double the height of the car How does the potential energy change?
If it were raised twice as high, how much more potential energy would it have? It would have twice as much potential energy. Two cars are raised to the same elevation on service-station lifts.
When Joshua brakes his speeding bicycle to a stop kinetic energy is transformed to?
When Joshua brakes his speeding bicycle to a stop, kinetic energy is transformed to thermal or heat energy.
How much work is done on a satellite in a circular orbit about Earth?
The work done by the gravitational force is zero. This is because the satellite is moving in a circular orbit. Thus the direction of displacement of the satellite is perpendicular to the force of gravity. Hence work done is zero.
How much work is done when you push a crate horizontally with 100 newtons across a 10 meter factory floor?
If you push a crate horizontally with 100N across a 10m floor and the friction between the crate and floor is a steady 70N, how much kinetic energy does the crate gain? 12. ΔKE = work done = (100 N – 70 N)(10 m) = (30 N)(10 m) = 300 Nm = 300 J.
How many times more work is required to stop the car now that it is going twice as fast?
Note that the speed is squared, so if the speed of an object is doubled, its kinetic energy is quadrupled (22 4). Consequently, it takes four times the work to double the speed. Also, an object moving twice as fast takes four times as much work to stop.
How does the work done on a machine compared to the work done by a machine?
How does the work done on a machine compare to the work done by a machine? Because of friction, the work done by a machine is always less than the work done on the machine. What changes can a machine make to a force? Size of force; direction of force; distance through which a force acts.
What conditions must exist in order for a force to do work on an object?
In order for a force to qualify as having done work on an object, there must be a displacement and the force must cause the displacement.
How much energy is dissipated in braking a 1000 kg car to a stop from an initial speed of 20 m s?
Thus the KE is 1000 nt * 200 m = 200,000 joules, as was shown in the previous answer.
How do you calculate KE?
In classical mechanics, kinetic energy (KE) is equal to half of an object’s mass (1/2*m) multiplied by the velocity squared. For example, if a an object with a mass of 10 kg (m = 10 kg) is moving at a velocity of 5 meters per second (v = 5 m/s), the kinetic energy is equal to 125 Joules, or (1/2 * 10 kg) * 5 m/s2.
What is conservation of mechanical energy?
The principle of conservation of mechanical energy states that if a body or system is subjected only to conservative forces, the mechanical energy of that body or system remains constant.
Has kinetic energy must be?
Kinetic energy must always be either zero or a positive value. While velocity can have a positive or negative value, velocity squared is always positive.
When you are traveling twice as fast your kinetic energy is increased?
The following equation is used to represent the kinetic energy (KE) of an object. This equation reveals that the kinetic energy of an object is directly proportional to the square of its speed. That means that for a twofold increase in speed, the kinetic energy will increase by a factor of four.
What is the reaction counterpart to a force of 1000 N exerted by the Earth on an orbiting communications satellite?
The forces “Earth pulls satellite” and “satellite pulls Earth” are a Newton’s Third Law action/reaction force pair, which means that they must be exactly the same size at all times. Therefore, if “Earth pulls satellite with a force of 1000 N”, the “satellite pulls Earth with a force of 1000 N” is the reaction force.
How much work is performed by the gravitational force on a satellite in near Earth orbit during revolution?
The total amount of (net) work done by gravity as a satellite makes a complete orbit is zero. The gravitational force has a component in the direction of the satellite’s motion as the satellite moves toward the Sun (or Earth, or whatever).
How much work is done by the force of gravity on a satellite moving around the earth?
The work done by the force of gravity on a satellite moving around the earth is zero.
How much work is done by the force due to gravity?
Answer. The work done by gravity is W=mgh.
What is the work if the force is 50 N and the distance parallel to the force is 5 meters?
Work = Force * Displacement in direction of Force, W=F⋅s , W=50⋅5 , W=250Nm .
How do you work out the force?
Force Formula The formula for force states that force is equal to mass multiplied by acceleration. So, if you know mass and acceleration, just multiply them together and now you know the force! The units for acceleration are meters per second squared ( m/s2), and the units for mass are kilograms (kg).
Why do you do no work on a 25 kg backpack when you walk a horizontal distance of 100 m?
Why do you do no work on a 25 kg backpack when you walk a horizontal distance of 100 m? You do no work because the backpack moves relative to you. Although no work is done on the wall, work is nevertheless done on internal parts of your body. Two people who weigh the same climb a flight of stairs.
